Specialized dairy cattle under tropical conditions present changes on physiology caused by environmental and handling aspects. These alterations of different functions affect the capacity to express genetic potential of production. The research was carried out at savanna of Bogotá, Colombia. Located at 2547 m above sea level, annual mean temperature 13 0C, relative humidity 80 % and annual precipitation685 mm. The study's main objective was to characterize the changes in hematic and hepatic functions of dairy cows during pregnancy, calving and lactation periods and under tropical highland conditions. Forty Holstein Friesian cows were included during their fifth, sixth, seventh and eight months of pregnancy day of calving and weeks 1,2,3, 4,8, 12, and 16 of lactation period. The results showed that hematocrit (HT), hemoglobin (HB), mean corpuscular volume (MCV) and mean corpuscle hemoglobin (MCH), presented significant changes (P <.o5) due to physiological fetal growth. During pregnancy and lactation, weight and concentration of hemoglobin of eritrocites were higher than the values reported by literature, which could indicate a special mechanism of adaptation to the low concentration of atmospheric oxygen in the site of the study. On calving day, a significant increase of HT, HB, MCH, an aspartate aminotransferase (ASAT) and a significant decrease of total protein (TP) and globulins (GLOB) were observed (P<.o5). This can be ascribed to the calving stress and to proteins use for production of colostrum. At birth and at the beginning of lactation significant increases of ASAT were found (P <.o5), a change related to fatty degeneration in liver. Primiparous cows presented the lowest concentrations of TR albumin (ALB), GLOB and urea, as the highest levels of MCV and MCH (p <.o5) pointing out different metabolic status in young animals. The present information describes changes and metabolic adjustments for pregnancy, calving and lactation, of dairy cows. In this way a change in liver functioning that ...